A material handling apparatus constructed in accordance with the present invention includes an improved force transmitting assembly for rotating a boom section about its central axis. There are many known material handling devices which utilize boom sections which are rotatable about their central or longitudinal axes. Some of these known material handling devices are disclosed in U.S. Pat. Nos. 3,700,126; 3,224,608; 3,042,234; and 2,541,045. Although the drive arrangements utilized to rotate the boom sections of these known material handling devices have been more or less satisfactory in their mode of operation, at least some of the known drive arrangements include relatively powerful and expensive low speed drive motors which are operated to rotate the boom section about its longitudinal axis. In addition, at least some of the known drive arrangements have been relatively bulky and utilized complicated motor and pulley arrangements to rotate the boom section.